And on a cold, rainy night in New England Sunday, the explosive rookie from Oregon proved to be the difference in a wild, epic 41-34 49ers victory over the Patriots in a duel between two of the NFL’s best teams.

After the Patriots had fought back from a 31-3 second-half deficit to tie the game 31-31 with a little more than three minutes left, James returned the ensuing kickoff 62 yards to the Patriots’ 38 yard line, setting up a go-ahead touchdown pass on the very next play from Colin Kaepernick to Michael Crabtree.

The touchdown and extra point put the 49ers up 38-31 and gave them a lead they wouldn’t relinquish. After holding the Pats on downs deep in New England territory, the 49ers added a field goal to extend their lead to 41-31, then weathered a Patriots field goal to cut the lead back to seven before securing the ball on an onside kick attempt to lock up the win.

The victory improves the 49ers to 10-3-1 and drops the Patriots – who had been a 5- to 5 ½-point favorite by oddsmakers -- to 10-4. The win also clinches a playoff berth for the 49ers for the second straight season and gives the Patriots their first home loss in December in 21 games.

Sunday night’s game actually was two games in one. The 49ers dominated early, going up 31-3 by the third quarter on three of Kaepernick’s four touchdown passes and a defense that had completely stymied the highest-scoring offense in the league.

Then, suddenly, the 49ers offense went cold and “Brady magic” took hold.

As the Niners went three-and-out on five straight drives, Patriots quarterback Tom Brady led four long scoring drives – of 92, 66, 86 and 73 yards -- cutting apart the No. 2 defense in the NFL in the process.

Only when James returned his kickoff did the 49ers suddenly spring back to life, with Kaepernick immediately connecting with Crabtree for the game-winner.

Kaepernick finished with 216 yards passing on 14-of-25 passing, for the four TDs and one interception as the Niners put up 383 yards of total offense (including 180 on the ground).

The Patriots dwarfed that number, putting up 520 yards – but lost the game.

Now, the 49ers will go to Seattle next Sunday for another nationally televised game, this one against NFC West contender Seattle (10-5), a 50-17 winner over Buffalo this weekend.

One concern for the 49ers will the health of All-Pro defensive end Justin Smith; he had to leave the game and his status is uncertain for this week.